OCC Commands = DatabaseException: Invalid database type

Steps to reproduce

1./var/www/owncloud# sudo -u www-data php occ maintenance:mode --off
2.
3.

Expected behaviour

Tell us what should happen

Actual behaviour

Tell us what happens instead
An unhandled exception has been thrown:
OC\DatabaseException: Invalid database type in /var/www/owncloud/lib/private/Server.php:549
Stack trace:
#0 /var/www/owncloud/lib/composer/pimple/pimple/src/Pimple/Container.php(118): OC\Server->OC{closure}()
#1 /var/www/owncloud/lib/private/AppFramework/Utility/SimpleContainer.php(108): Pimple\Container->offsetGet()
#2 /var/www/owncloud/lib/private/ServerContainer.php(86): OC\AppFramework\Utility\SimpleContainer->query()
#3 /var/www/owncloud/lib/private/Server.php(1259): OC\ServerContainer->query()
#4 /var/www/owncloud/lib/private/Server.php(424): OC\Server->getDatabaseConnection()
#5 /var/www/owncloud/lib/composer/pimple/pimple/src/Pimple/Container.php(118): OC\Server->OC{closure}()
#6 /var/www/owncloud/lib/private/AppFramework/Utility/SimpleContainer.php(108): Pimple\Container->offsetGet()
#7 /var/www/owncloud/lib/private/ServerContainer.php(86): OC\AppFramework\Utility\SimpleContainer->query()
#8 /var/www/owncloud/lib/private/Server.php(1189): OC\ServerContainer->query()
#9 /var/www/owncloud/lib/private/Server.php(607): OC\Server->getAppConfig()
#10 /var/www/owncloud/lib/composer/pimple/pimple/src/Pimple/Container.php(118): OC\Server->OC{closure}()
#11 /var/www/owncloud/lib/private/AppFramework/Utility/SimpleContainer.php(108): Pimple\Container->offsetGet()
#12 /var/www/owncloud/lib/private/ServerContainer.php(86): OC\AppFramework\Utility\SimpleContainer->query()
#13 /var/www/owncloud/lib/private/Server.php(1457): OC\ServerContainer->query()
#14 /var/www/owncloud/lib/private/legacy/app.php(344): OC\Server->getAppManager()
#15 /var/www/owncloud/lib/private/legacy/app.php(108): OC_App::getEnabledApps()
#16 /var/www/owncloud/lib/base.php(590): OC_App::loadApps()
#17 /var/www/owncloud/lib/base.php(1070): OC::init()
#18 /var/www/owncloud/console.php(74): require_once(’/var/www/ownclo…’)
#19 /var/www/owncloud/occ(11): require_once(’/var/www/ownclo…’)
#20 {main}root@Owncloud2022:/var/www/owncloud#

Server configuration

Operating system:

Web server:

Database:

PHP version:

ownCloud version: (see ownCloud admin page)

Updated from an older ownCloud or fresh install:

Where did you install ownCloud from:

Signing status (ownCloud 9.0 and above):

Login as admin user into your ownCloud and access 
http://example.com/index.php/settings/integrity/failed 
paste the results into https://gist.github.com/ and puth the link here.

The content of config/config.php:

Log in to the web-UI with an administrator account and click on
'admin' -> 'Generate Config Report' -> 'Download ownCloud config report'
This report includes the config.php settings, the list of activated apps
and other details in a well sanitized form.

or 

If you have access to your command line run e.g.:
sudo -u www-data php occ config:list system
from within your ownCloud installation folder

*ATTENTION:* Do not post your config.php file in public as is. Please use one of the above
methods whenever possible. Both, the generated reports from the web-ui and from occ config:list
consistently remove sensitive data. You still may want to review the report before sending.
If done manually then it is critical for your own privacy to dilligently
remove *all* host names, passwords, usernames, salts and other credentials before posting.
You should assume that attackers find such information and will use them against your systems.

List of activated apps:

If you have access to your command line run e.g.:
sudo -u www-data php occ app:list
from within your ownCloud installation folder.

Are you using external storage, if yes which one: local/smb/sftp/…

Are you using encryption: yes/no

Are you using an external user-backend, if yes which one: LDAP/ActiveDirectory/Webdav/…

LDAP configuration (delete this part if not used)

With access to your command line run e.g.:
sudo -u www-data php occ ldap:show-config
from within your ownCloud installation folder

Without access to your command line download the data/owncloud.db to your local
computer or access your SQL server remotely and run the select query:
SELECT * FROM `oc_appconfig` WHERE `appid` = 'user_ldap';


Eventually replace sensitive data as the name/IP-address of your LDAP server or groups.

Client configuration

Browser:

Operating system:

Logs

Web server error log

Insert your webserver log here

ownCloud log (data/owncloud.log)

Insert your ownCloud log here

Browser log

Insert your browser log here, this could for example include:

a) The javascript console log
b) The network log 
c) ...